Spatial processing such as multiple-input and multiple-output (MIMO) techniques are important for improving the performance of wireless systems. In environments with low angle spread, higher-order sectorization has been shown to be effective for increasing throughput. More generally, user-specific beamforming can be used to multiplex signals for different users.
However, the problem is to achieve higher-order sectorization or user-specific beamforming with an efficient and visually unobtrusive antenna architecture. Conventional solutions use antenna elements arranged in a linear array. For sectorization, each sector is created using a single linear antenna array where the sector size is inversely proportional to the width of the array. As a result, a large number of wide panels is required for higher-order sectorization. Also, for user-specific beamforming, beam patterns that are far from the boresight direction of the antenna elements have poor radiation pattern characteristics.
Due to the physical implementation of the conventional linear array, the conventional architecture imposes restrictions on the installation and deployment, potentially creating a visually obtrusive object.